Rotorua police youth services Sergeant James Harvey said in Rotorua police were seeing the same crimes being committed, they were just being committed by younger people.
"Ten years ago we were seeing 16 and 17-year-olds committing the more serious crimes, now we're seeing 12 and 13-year-olds committing those crimes.
"There are also now a lot of drugs in that age group, which we weren't seeing there previously."
Harvey said early prevention was the key and children between 10 and 13 were at a crucial age.
"Personally I think the legislation is due for an overhaul. The kids have outgrown a legislation which really wasn't built for children under 14.
"These are kids who come from bad backgrounds and we almost need a middle man working between the care and protection and youth justice space."
The report also showed of children between 10 and 13 who committed crimes, 97 per cent of boys and 100 per cent of girls referred for a family group conference had previously been the subject of a report of concern to Oranga Tamariki.
"These kids had already been identified, and whatever intervention was there, it didn't work," Harvey said.
"These are the ones we should be intervening with. The moment they come to our attention is when they need our assistance."
Principal Youth Court judge John Walker said if New Zealand really wanted to be serious about youth crime, it needed to tackle issues when offenders were children, "not when they turn up in the youth justice system at 14".
A key issue the report highlights is that the causes of youth crime are intergenerational and linked to problems within families and communities, he said.
"When the research shows that 80 per cent of child and young offenders grow up in homes where family violence is present, breaking this cycle of violence from one generation to another is critical.
"We need to be pre-emptive, responsive, and adopt long-term strategies.
"Regular visits to check on the health of toddlers, programmes to help parents and address the mental health of mothers, tackling challenging behaviour by children and supporting early childhood centres and schools are just some of the options the report highlights for addressing the issues that lead to youth offending."